Unit 1 1
Unit 2 6
Unit 3 9
Unit 4 13
Revision Exercises (Unit 1— Unit 4) 17
Key to Revision Exercises (Unit 1— Unit 4) 26
Unit 5 30
Unit 6 34
Unit 7 38
Unit 8 42
Revision Exercises ( Unit 5—Unit 8) 46
Key to Revision Exercises ( Unit 5—Unit 8) 55
Unit 9 59
Unit 10 65
Unit 11 69
Unit 12 75
Revision Exercises (Unit 9—Unit 12) 79
Key to Revision Exercises (Unit 9—Unit 12) 87
Unit 13 90
Unit 14 95
Unit 15 98
Unit 16 103
Revision Exercises (Unit 13—Unit 16) 107
Key to Revision Exercises (Unit 13—Unit 16) 115
Key to Exercises (Unit 1—Unit 16) 119
Key to Revision Exercises 131
Key to Supplementary Reading Exercises 137
课文参考译文 139